At the 140conf conference in LA, Jeff Pulver asked me to think about the future of Twitter and even though I obviously have no crystal ball, I took some risks and here you go, I gathered my predictions here, in the form of "tweet slides" so you might want to watch the video too. Some of those predictions were suggested to me by my friends on Twitter, let me know if I missed one credit as I prepared it… in realtime).
It will reach masses of people
They won’t use the same tools as we do
It will not be only about Twitter
-status updates will be open across social software
-all social software will have status updates
-Facebook has 40+ million updates a day
Twitter will still be dominant
in status updates
it's the motherboard on which we plug in
We will laugh thinking we were updating them all manually
The social graph will also open up
Twitter will be big to get an idea of a person or a brand reputation
not by number of followers but mostly influence with retweeting and lists
lets you think like that person thinks
Twitter will replace SMS for millions of people
-it is portable and archives across devices
-you don’t need to remember a phone number
-you are not tied to a mobile operator
Twitter might replace Chat for many people, too
-a DM exchange is very similar to a private chat
-Twitter lists are very similar to a public chat room
Location will be one of the most widespread status update
Private updates will be bigger than public updates
(my kids say…)
Public ecommerce
status updates won’t work
buying things is very intimate
Live reviews of any place and product will deeply influence it though
Promos by brands and retailers will have big success for last minute deals
Talking to shops and restaurants via Twitter will become standard
and will get opt in coupons as we enter a shop, based on location
Web will be a fraction of mobile use
Dating over Status updates won’t be big
Twitter won’t display ads in your main feed
Users will get too angry at unsolicited ads
Other revenue opportunities such as pro accounts for businesses will be enough
There will be more devices publishing updates than humans
wifi scale, planes, trains, cars all posting updates
Corporations will have entire teams devoted to Twitter and status updates
Hyperlocal news sites with Twitter geotagging feature
(thanks, @stevefarnworth)
Google and Bing will be the dominant ways to search Twitter
Google will have its own Twitter and won’t acquire Twitter
There will be a few alternatives for niche search such as brand monitoring
Internal Enterprise Twitter like services will become standard
Vertical Twitter apps will start to appear
Stocktweets is the first one
Twitter will remain mostly used outside of Twitter.com
Language will evolve adapting to 140char, concise, ignore rules (thanks, @bernard_d)
@mentions spam will grow and become a tough to solve issue
There will be less and less bullshit in public events and in general
It will always be about you, not the tools
Oh and that makes 34 predictions, not 30, a few more came in last minute 
add yours in comments!